Conventional communication cables for both riser and plenum applications typically include a number of insulated conductors that are twisted together in pairs 100 and surrounded by an outer jacket 102, as seen in FIG. 1. Crosstalk or interference often occurs because of electromagnetic coupling between the twisted pairs within the cable or other components in the cable, thereby degrading the cable's electrical performance. Also, as networks become more complex and have a need for higher bandwidth cabling, reduction of cable-to-cable crosstalk (alien crosstalk) becomes increasingly important.
Barriers or separators, such as the separator 110 shown in FIG. 1, are often used, particularly in plenum applications, to separate and isolate the pairs of conductors, thereby reducing crosstalk interference. Such barriers and separators are normally made of a flame retardant insulation material or insulation materials that meet cable burn tests, such as fluoropolymers like FEP in the case of plenum cables tested per the requirements of NFPA 262 and flame retardant polyolefins in the case of riser cables which are tested per UL 1666. In other applications, such barriers also need to meet requirements for standards such as tests for Low-Smoke, Zero-Halogen or other burn tests similar to UL 1666 or NFPA 262.
However, such flame retardant insulative materials are typically halogenated and release toxic halogens when burned. Fluoropolymers in particular melt and drip when burned. Also, fluoropolymers are typically more expensive due to high demand.
Therefore, a need exists for cable components that meet industry standard burn requirements and that are less toxic and less expensive.